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1988 Silver Jubilee 25/50 Anniversary Head

Discussion in 'Marshall Amps' started by 67Mopar, Apr 7, 2019.

  1. 67Mopar

    67Mopar Well-Known Member

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    I've owned my '87 Marshall Silver Jubilee 2550 for 6 years, and just discovered it's not a 1987 model. It's a 1988! Odd that I never bothered to match the transformer date codes to the inspection label. I was told that several were made in 1988, but this is the first one I've seen. Kind of cool, historically.

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    Last edited: Apr 7, 2019
  2. mickeydg5

    mickeydg5 Well-Known Member

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    The originals were manufactured from 1987 to 1988 in silver tolex.

    Mine are/were from 1987.
     
  3. mickeydg5

    mickeydg5 Well-Known Member

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    The black tolex versions started in 1988.
    Then came Slash.
     
  4. mickeydg5

    mickeydg5 Well-Known Member

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    What is your serial #?
     
  5. 67Mopar

    67Mopar Well-Known Member

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    07477
     
  6. mickeydg5

    mickeydg5 Well-Known Member

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    Yes, well after the major revisions and into 1988.
     
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  7. 67Mopar

    67Mopar Well-Known Member

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    What all did they revise?
     
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  8. mickeydg5

    mickeydg5 Well-Known Member

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    I am speaking of the several board revisions that made earlier Jubilee sound sad and sterile.

    I had one early board that I doctored and realigned to sound the way it should.

    Stupid Marshall. :noplease:
     
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  9. 67Mopar

    67Mopar Well-Known Member

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    I remember playing one when they were first released, but it didn't do anything for me. My friend Joe had a SJ combo that totally blew me away! Mine has a lot of bottom-end, no doubt about that. The first one I played seemed like it lacked bottom. Maybe it was the room, I don't recall?
     
  10. mickeydg5

    mickeydg5 Well-Known Member

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    No, that was the bad board trace and connection design.
    Mine sounded like that with hardly any bottom and sterile.
    I modified the board to realign signal paths and proper switching between channels and it is one of the best Jubilee amplifiers I have ever heard, one of the best musical amplifiers I have heard period.

    By the way that was a 2554, no choke - 100R 25W resistor instead.
     
    Last edited: Apr 8, 2019
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  11. 67Mopar

    67Mopar Well-Known Member

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    So, there were some significant changes along the way then. I didn't know this? I had heard there was a change to the loop, but that was it. I don't normally dig effects loops, but the SJ loop sounds fabulous.
     
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  12. mickeydg5

    mickeydg5 Well-Known Member

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    The amplifier's electronic design barely changed being the only changes that I had noticed were the supporting components for the switching for transitioning between channels. The board layout design changed there as well.

    It would seem that various boards were either made by different suppliers or there were different modeled boards to mass produce because it was a hit or miss. Some people found and heard good amplifiers while others got the not great sounding ones. It all got straightened out in 1987 I believe, whenever they hit the 3000 and something number.
    I have never heard anything about a recall, as usual.

    The effects loop is a nice one and all tube. The only thing nicer would have been some level mixing capability but it works good as is designed.
     
    Last edited: Apr 8, 2019
  13. DarylD

    DarylD New Member

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    I have a JCM Slash. I am looking for a Bottom SLASH cab. Can anyone help?
     
  14. Mitchell Pearrow

    Mitchell Pearrow Well-Known Member VIP Member

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    :welcome: To the forum
     
  15. jupiter89

    jupiter89 Active Member

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    I hope this helps. Back about 2012 I was reading about the vintage Jubilees, and saved this commentary. I wish I had the members's name to give him credit, but unfortunatedly didn't save it. It appears the serial number the best clue for determining the more preferable circuit.


    From Marshall Forum thread:

    Re: Different Jubilee circuits???



    "As the theory says the latter made jubilees tend to have more gain and a richer,fuller and overall 'meatier' sound this might have to do with the post #03100 circuit type and therefore be the technical, if not evidence, then indicator of the veracity in the claim about different jubilee circuits.


    Serial numbers Above 03100 have a tweaked curcuit that makes the amp sound fatter & warmer. This means most 87 silvers and all 88/89 black jubes (& slash sigs) have the later curcuit. I've owned a pre-03100 2558 combo and it sounded tame compared to all the other jubes I've owned (around 10no various models).

    My advice would be avoid low serial jubilees or find someone to mod to the later curcuit if the only amp you can find is an earlier serial.



    The 03100+ thing is not the only time Marshall have factory tweaked an amp whilst still in production. Also, I have even seen variants of the Jubilees within later serial ranges which were tweaked at the factory to a slightly different schematic than the standard. (effects loop/preamp section altered) if I remember correctly.



    I think you should trust your ears not read utter shite that is dished out on internet forums regarding the 3100 thing.


    If the 87 2555 has a serial below 03100 it has a slightly different curcuit. The more desireable fatter sounding jube is the later curcuit found on most silvers and all black jubilees. If you have one of the early serials it can be converted to a later curcuit with a few component changes "



    That being said, I think somewhere I have the Marshall circuit diagrams of both the pre- and post 03100 circuits and will post when I find it. I have to re-learn how to post a picture via a URL though. It's a pic I saved, and not on a website so there is no URL which is necessary to post pics.
     
    Last edited: May 15, 2019
  16. lespaul6

    lespaul6 Active Member

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    Another problem Ive noticed with the original 2555's is that they develop a problem where if you vibrate the board or move it by wiggling the input jack the sound/gain will fade in and out... Ive had two jubes do this exact same thing and I couldn't find a tech that could figure out why this was happening. It was not the input jack or the soldering but something else entirely .. anyone else have this problem with a Jubilee?
     
  17. 67Mopar

    67Mopar Well-Known Member

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    Those encapsulated type jacks used on the SJ get dirty, fast! I don't know what causes it, but my Cornford's were the same way. I clean the jacks 3 times a year, minimum. Some form of electrolytic reaction between the contacts and humidity, maybe? Routine cooking emits oils into the air which combines with dust, so there is that as well. If it's visible on a coffee table, it's likely building on the contacts.

    I completely rebuilt preamp stages 1 and 2 in my RK1OO, because of this issue. In the end, it was a gummed-up input. I had cleaned the input, but not good enough.:wallbash:

    It's been said that silver can Deoxit leaves no lubricants behind... In my experience, this isn't entirely true. Clean the contacts with Deoxit, then use 9O% alcohol, and let it thoroughly dry before powering the amp.
     
    Last edited: May 15, 2019
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  18. mickeydg5

    mickeydg5 Well-Known Member

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    Does anyone know where to get or have an early release 0 or 1 issue schematics of the 2550 or 2555 amplifiers? All sorts of people bring these differences in circuits up but I have yet to see any proof.
     
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  19. jupiter89

    jupiter89 Active Member

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    67Mopar: That is great advice you gave when cleaning the jacks with Deoxit or any product to use 90% alcohol afterwards. It makes sense because once cleaned the leftover solution, oxidation and/or crud will be sitting there and could cause the same problem eventually. A word of caution though: avoid getting alcohol on any wiring insulation, and if so wipe it up right away. I am not sure, but the alcohol may degrade the insulation, If I'm wrong about that's, fine, but why risk it.
     
  20. lespaul6

    lespaul6 Active Member

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    I should mention, in both cases the cliff jacks were replaced and the problem persisted... we could not crack the source.. it was very frustrating at the time and remains a mystery as to the cause.
     

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